Adjustable camera back



5 Sheets-Sheet 1 Filed March 31, 1950 5 Mw @d 5 3 5 l U/ I. 3 .TY/wuI a l, f ...5% L oe, a o e lo. @c to! Aoco 0 m M8 Gunn/v MNM M 2 5/ oa /o o 2 hw o 5 o nu ,m Ur 2 o ,W 7

W o w P HJ o Mm A M 1% 2 Il U, 7 7 N W 7 5 3 Fw) a 7 5 T 0 S 7. ha o u 4 a q n Hoa. F ist eee fue o o L. o 5 H3 ATTORNEY C. R. GREGORY ADJUSTABLE CAMERA BACK July 31, 1951 Filed March 31, 195o 5 Sheets-Sheet v 2 INVENTOR ATTORNEY July 31, 1951 c. R. GREGORY 2,562,312

ADJUSTABLE CAMERA BACK Filed March 31, 1950 5 Sheets-Sheet 5 Ig-C -E ATTORNEY July 31, 1951 c. R. GREGQRY ADJUSTABLE CAMERA BACK 5 Sheets-Sheet 4 Filed March 3l, 1950 I -l j c. R. GREGORY ADJUSTABLE CAMERA BACK July 31, 1951 5 Sheets-Sheet 5 Filed March 31, 1950 Patented July 3l, 1951 UNIT-ED .STAT-Es PATENT oFFIcE :2,562,312 v `ADJUSTABLE CAMERAS BACK Cresswell Redvers Gregory, Montreal, Quebec, .Canadauassignor to Bomac' Correctone-Process Limited, Toronto, Ontario, Canada Application Marchal, 1950,;seria1kNaf153,044

.The vvinvention relates `to .improvements -in fan adjustable camera back-as described in the-present specification `and illustrated fin* the accompanying drawings that-forma part-of the same.

j. The invention-,consists essentiallyof lthe novel features of )construction .as pointed out ybroadly and-specifically in thefclaims rfor novelty following-a description containing anvexplanation in detailof an acceptable form of the invention.

rPhe robjects of the invention are to provide an adjustable camera baclcwhichwill substantially holda photographic plate absolutely :firm in any adjusted vpositionv and ,-in.which vibration will be minimized -during the mounting and positioning of this plate; to furnish acameraback whichwill be easily adjustable and -in Ywhich the various ad- .iustments will beeasily assembled and simple to operate; to contrive an Vadjustable camera back which -will facilitate.the'positioning ofa photographic plate therein 'under any conditions, i such as in a dark room -or `the like; VVto devise an adjustable camera frameI which may be used with a back or without a vback-de1; ending on whether the frame is being usedat the rear or the `front ofa camera and :in which thecframe willbe independently capablev of positioning one ormore photographic plates precisely in lpositiontherein ;v to-makeran adjustable camera `back .in which a number of vplates may be secured .in any; position therein adjacent to oneianother and in which these plates may :be of any suitable commercial size ;4 to assemble an-adjustable camera back infa camera in :which the Vvarious partswill be simple inxconstruction and inexpensive, to manufacture; and 'generally .to .provide an r.adjustable camera back .which will firmly ,-holdone or more plates .in any suitable position thereiny and which willbe eicient for its purpose.

In the drawings:

Figure 1 is a perspective view showing the adjustable camera back A.and the cover therefore mounted on the rear of the` camera.

Figure '2 is a front view of the `adjustable camera backwith its cover removedand showing a plate being held in :position therein.

Figure 3 `is an enlarged front View showing the frame of the adjustable camera back-with the upper-'and lower. support bars' removed therefrom.

Figure-f4 is an enlarged' front'view ofthe upper adjustable support bar and showing the plate clamp. in a closedpos'iticn.

xliigurev 5 is :an enlarged frontview lof 'the lower adjustable .-support :bar :and showing the plate clamp inafclosed position. Al-igure cis anenlarged sectional planviewoi-.the

v"2 loweradjustabley support bar as taken on the line 6 6 in Figure2. f

Figure 7' is an enlarged sectional vplan detail through one end of the upper adjustable support bar as taken on the line ,1 1 in Figure 2 :and showing the lock bolt in the end thereof inA an `engaged ,position with respectto theframe of the adjustable camera back.

Figure is an enlarged sectional vertical detail as taken on the line B-Sin'Figure 4 and showing the plate clampon the upper adjustable 'support bar in a closed-position and holding a photographic plate-firmly against a plate 4`rest ron' the device.

. Figure 9 isv an enlarged sectional detail similar to aFigure`8, `but showing *the platel clamp in `an open position.

Figure 10 is an enlargedsectional vertical detail as, taken onthe line IU-I 0 inv Figure -4 and showing the adjustable screw for vvarying the position of .an adjustable insert 'located' on the inside edge of the adjustable support bar.

` Figure 11 is an enlarged. sectional vertical detail as taken. onthe line l I-l I in Figure 2 and'showing vthe cones. andvcone settings that lare used to hold 'the 'adjustable support ybars in rigid alignment.

"Figure, 12 V'is an` enlarged fragmentary sectional view as taken on 'the line I2-I2 in Figure 4 and showing"thecons'truction of the cushionrollers mounted on the plate clamp bars.

i Figure 13 is an enlarged fragmentary frontview showing the left hand plateholder which allows for horizontal and vertical adjustment of the photographicplate.

Figure 14 .is `an enlarged ,fragmentary front view `'showing the righthand plate holder which allowsfor horizontal adjustment of the photographicy plate.

l Figure- 15 is valsectional detail as. taken on the line! lI5-'l5 .in'Figure 13 and showing the spring and roller oniwhich the edge of the plate rests.

`.-Fig,ure 16 is-an enlarged' fragmentary rear view showing 'the left `hand plate holder vand the mannerin which fthe vspring is secured thereto.

l,Figure 1 7-is asectionalldetail as taken on fthe line. I'l-I'I .in Figure 14 and showing themanner in .whichtheplate holders are secured to an Yadjustable insert.

-Figure 18 is anenlarged fragmentary. perspective viewshowing al portion of the lower support har .in; which .the Vadjustable insert therein., is moved toan extreme inner position by means of a` tool.

' "Eig-ure: 19 yis a. .persp'ective view of Vthe-tool .used

for effecting all the adjustments necessary with respect to the adjustable support bars, the adjustable inserts, and the plate supports.

Figure is an enlarged fragmentary sectional. detail as taken on the line 2li-20 in Figure l and showing the construction of the upper portion of the frame of the adjustable camera back and the cover therefor.

Figure 2l is an enlarged fragmentary sectional detail as taken on the line 2|2| in Figure 1 and showing the construction of the lower portion of the adjustable camera back and cover therefor.

Like numerals of reference indicate corresponding parts in the various figures.

Referring to the drawings, the camera as illusstrated in Figure l consists of a base having a lens frame 26 and a rear support structure 21 suitably supported thereon, and this lens frame and rear support structure are connected to one another by bellows 28. The adjustable camera back 29 consists of a frame 30 which is suitably mounted on the back of the rear support structure 21 and has a cover 3| movably secured to the rear portion thereof.

The frame 30 of the adjustable camera back 29 consists of horizontal cross members 32 and 33 and vertical side members 34 and 35 which are xedly secured to these horizontal cross members thus forming a rectangular frame or structure. The cross section of the vertical side members 34 and 35 is of a T-shaped formation and the horizontal cross members 32 and 33 are of a rectangular formation. The horizontal cross members 32 and 33 have holes 31 extending horizontally therethrough and the front face of these cross members are countersunk. The flanged portion of the T-shaped Vertical side members 34 and 35 have holes 38 extending horizontally therethrough, or at right angles thereto and these holes are countersunk on the front edge of this flanged portion. The holes 31 and 38 in the cross members and vertical side members, respectively, provide a. means of fixedly securing the frame 30 to the rear support structure 21 of the camera.

A plurality of holes 39 extend through the web of the T-shaped vertical side members 34 and 35 and these holes are counter sunk on the front surface of the web. A plurality of horizontal holes 4D extend partly through. the front flanged portion of the T-shaped vertical side members 34 and 35. These holes 4D are drilled a suitable distance into the inner face of the outer flange portion at a slight angle so that the blind end end. The holes 39 and 43 in the web and flanged portions, respectively, of the vertical members 34 and are suitably spaced apart to coincide with is closer to the rear of the frame than the open positioning and locking means on the upper and lower adjustable support bars 4| and 42. These adjustable support bars 4| and 42 consist of an upper and lower cross bar 43 and 44 respectively. Each of the cross bars 43 and 44 which form the body of the upper and lower adjustable support bars 4| and 42 are of a somewhat I-shape, in that they each have a central portion with top and bottom flanges projecting outward from both surfaces thereof, and the bottom portion of the upper cross bar 43 is cut away and the upper portion of the bottom cross bar 44 is also cut away to permit the mounting of adjustable inserts 52 and 53. The central portion of each of the cross bars 43 and 44 adjacent the cutout portion is of a rectangular solid formation. Each of the cross bars 43 and 44 have lock plates 45 xedly secured to the front face towards the ends thereof, and these lock plates extend outward past the ends of the cross bars. The extending portion of each of the lock plates have a pair of cones or tapered pins 46 extending outward from the inner surface thereof. Each of the lock plates 45 also have a lock bolt 41 slidably fitted therein and adapted to extend outward longitudinally past the ends of these plates. Each of the lock bolts 41 consists of a body portion 48 and a tapered end portion 49 extending outward therefrom. A knob 50 is xedly secured on the inner end of the body portion of each of the lock bolts 41 providing a means of manually operating the same. A stop pin 5| is located towards each end of the cross bars 43 and 44 and in alignment with the lock bolts 41 so that they may eng-age the latter when the same are moved to an unlocked position. The cones 46 extend outward from the lock plates 45 and are adapted to engage in the cone-like or countersunk holes 39 in the web portion of each of the T-shaped vertical members 34 and 35 for the purpose of positioning the upper and lower support bars 4| and 42, and at the same time the tapered end portion 49 on each of the lock bolts 41 are engaged in the holes 40 in the flanged front portion 0f these T-shaped vertical members. As these holes 40 are drilled at an angle that coincides with the tapered end portion 49 of the lock bolts, these bolts tend to tighten the cones 46 against their respective seats in the cone-like or counter sunk holes 39 thus holding the support bars in a rigid position. In this manner each of the adjusting support bars 4| and 42 may be definitely located and locked in any suitable position with respect to the frame 3U and the latter has numerals depicted on the inner surface of the web portions of the T-shaped vertical members thus enabling the operator to know exactly the position in which he should place the support bars for a particular size of photographic plate before eny gaging and locking same in position.

The adjustable inserts 52 and 53 which are located in cutouts in the upper and lower cross bars 43 and 44 are held in position by threaded studs 54 which engage with threaded caps 55. In this respect the threaded caps 55 are fixedly secured to the upper and lower cross bars toward each end thereof and each have a semi-circular tapped hole 56 extending therethrough. Each of the threaded studs 54 are accommodated in a recess 51 in the ends of the adjustable inserts and are free to turn within this recess and the semi-circular tapped hole 56 in the threaded cap fits over the recess 51 and the studs 54 therein. A semi-circular cutout 58 is located in the adj ustable inserts directly opposite the semi-circular tapped hole 5E in the threaded caps 55 thereby permitting a tool to be inserted therein for turn-V ing the threaded studs 54. As these threaded studs 54 are turned in either direction they engage with the semi-circular tapped holes 56 in the threaded cap 55 and accordingly move the end of the adjustable insert either inward or outward with respect to the upper or lower cross bar 43 or 44. The adjustable inserts 52 and 53 are secured in the center thereof by means of a pin extending into the upper or lower cross bar and a washer is located between the adjustable insert and the cross bar thereby raising the upper edge of this insert slightly above the edge of the cross bar thus permitting the threaded caps and threaded studs to substantially bear on and effectively hold theends ofthe inserts in any ad justable position. A- at holdingstrip- 59v is flxedly. secured to the far side of the adjustable inserts 52 and 53and extends past the inner edges thereof thus providing a backing against which a photographic platefmaylbe held'. A-` spring catch 60 ismounted in a vrecess in a lower ed'geof the upper cross-bar 43 and is held in position by means` of a stud 6|' anda compression spring 62. This spring catch is adapted to'V bear down on. the upper edge of a photographic plate when the same has been placed adjacent the iiat holding strip 59 and tendsl t'o gently hold thev upper end' of this: plate in position.

Avr platev clamp 63' and 64 is mountedv on Vthe upper and' lower crossbars 43 and 44, respectively, and it is adapted to bear against the rear face or a photographic plate along the upper and lower lportions thereof. Each of these plate clamps 63`and 64 consistsofa rod 65 which extends parallel to the cross bar andy is movably supported on the arms 66. Inv this respect,V the rod65 is flxedly secured with respect'to therarms 66 and the opposite ends of the latter arepivotally mounted on a bracket 61 secured to the cross bar, vand' a pin 68y which. extends through part of the: same.- 'A stop-69A also extends through thisbracket 61` so asv to determinethedistance that the arms 66 may swing upward. AA pair of sleeves 10 are slidably mounted on therod- 65 and resilient rollers or rubber cushions 1| are fixedly secured on thesesleeves. A- leverA 1.12 is pivotally mounted on the opposite end of the bracket 61 to that of the arms 66 and a spring 13 is connected to thelever 12 and-the arms 66.

It will; be seen in-Figfure 9V that when the lever '12 is raisedy or lowered thearms 66 are also raisedor lowered. As` the lever 12 is lowered or closed to; a certain position the pivot point of. the lever,

the pivot point of the spring in the lever, andA the point of connection` of. the spring. to the arms `will bein line .and as the lever is closed or loweredv further the pivot point of thev spring in the lever passes this neutral line and tends to lreepv the lever in a closedI position. If the lever held in aV closed position by the spring pressure, a .pressure will also be exerted on the arms. Due to the fact that the vpressure applied, by the spring 13 must not be too great and also that it is used as a positive link duringy a portion of its operation the spring is made of a single piece of wire formed to apdouble U-shaped or an elongated oval formation. This shape of spring allows for a positive connection between the lever and arm, and at the same time allows for spring action when the sides are compressed towards eachother. The spring 13 is held in the. arms 66. by means of cotter pins .and in the lever 12 it mounted in slotsand held in. position in these slots by meansof a screw 13A. j

A left hand plate holderl 14v and a right hand plateholder 15 are movably mountedron the upper and lower adjustable inserts 52 and 53, and serve:

as holding and levelling devices for adjusting the position of a photographic .plate in the camera.

The left hand` plate holder consists of a base 16 which is movably secured to the adjustable insert 53 and secured inposition by means of a screw 11 which is adapted to be threaded into any one of a number of tapped holes 19 which aresuitably spaced apart along the left .hand portion ofvthis adjustablel insert.. ,Positioning holes 19 arer located on each side of the tapped holes 1.8 and are adapted to be engaged by a. pair of pins-'80*which are* flxedlysecured in the base 16 e Y i and in conjunction with the-screw 11 subs't'an:1 tially holds. the left hand plate holder Hin pos. sition with` respect to theadjustable insert 53..

A. vertical adjusting means 8l' is mounted on the base 16. and consists. of ashaft 82. which.y ex-I tends. through a portion of. the base 1.6 and a ringer grip 03 is fixedly secured on. the outer end of. thisV shaft.. An annular groovel 84 is cut. in' the shaft 82A and. a retaining ball l85v is held', inengagement therewith by means of a compression spring; 86 thus permitting the shafty 82 to turn and at, the same time preventing it fromv beingremoved from thebase. A pair of Stop-pins 81 are fxedly secured in the base andy project outward therefromA at each:V side ofY theshaft 8 2.- and these pins engage, the. linger grip 83 when thesame is turned a` predetermined distance in; either; direction. An eccentric pinY 88 is iixedly' secured in the innervend ofthe shaft 02, and a satinspring 89 lies over this eccentric pin 88 and is raised or lowered by thelatter as the shaft 82; turned, thus providing av means of vertically ad justing a photographic plate resting thereon.

The horizontalv adjusting means 90 consists of a shaft 9| which extends through a raisedl portion of the base 1.6; and is held in position by a, retaining ball 92 engaging an annular groove therein, and a compression spring 93 bearing, against this ball. A linger grip 94 is xedly secured on the other end of the shaft 9|, and the distance that the latter may turn is deter-` mined by a stop pin 95 and a stop strip y96. An; eccentric pin 91y is secured in the inner end of the shaft 9| and a roller 98 is rotatably mountedon this. eccentric pin. This roller is adapted to engage the edge of a photographic plate and itsv position may be adjusted by turning the shaft. 9| thereby providing; a means of precisely adjusting the position of the photographic plate horizontally.

The vright hand plate holder 15 is movably secured on the adjustable insert 53 and is adapted to provide a means of vertically adjusting the position of the right-hand side of a photographic plate resting thereon. This right hand platev holder is provided with a screw and pins which engage in holes suitably spaced apart in the adjustable insert in a similar manner to that described inv the foregoing relating to the left handY y plate holder 14. In this instance the right hand plate holder consists of a base 99 having a shaft |00 extending through the upper portion thereof which is 'held in position therein by a retaining ball |0| 'and a compression spring |02 in a similar manner to the left hand plate holder 14. An eccentric pin |03 is secured in the end of the shaft |00 and a satin spring |04 lies over this eccentric pin and is raised or lowered by the latter upon the turning of the shaft |00. A iinger grip |05- is secured on the outer end of the shaft |00 and stop pins |706 are secured in the base and engage the finger grip |05 lwhen it is turned a suitable distance in either direction. The left hand and right hand plate holders 14 and 15 are adapted' to be moved laterally to any suitable position depending upon the width of the photographic plate when used and numerals are depicted on the top edge of the adjustable insert so asto enable the operator to easily and quickly determine the positions that these plate holders should be moved to depending on the size of the photographic plate being used.

Aiitting assemblyl |01 is provided in the vertical' member of the frame 30 and adaptedfor connection to a Vacuum 'arrangement as used for holding photographic plates substantially in contact with one another. This fitting assembly may be mounted in either side of the frame 30 and its position would be determined by the layout of the equipment being used in each installation.

The horizontal cross member 32 of the frame 30 has a longitudinal groove |08 in the underside towards the front of the cross member and this groove extends almost the entire length of the cross member. The cover 3| has a projection or tongue |09 extending along the top edge thereof and which engages in the longitudinal groove |03 in the horizontal cross member 32 of the frame when the cover is being placed in position thereon. A resilient strip ||0, which may be of a rubber or any suitable material, is adhered to the bottom edge of the cover 3| and projections cr tongues extend vertically along the inside face of the cover towards each side thereof. These projections or tongues fit inside the vertical side members 34 and 35 of the frame 30 to locate the cover longitudinally when the same is placed in position on the frame. A pair of fastening pins ll2 extend outward from the side edges of the cover 3| towards the bottom thereof and these are adapted to be engaged by hooks ||3 which are pivotally secured to the outer side of the vertical side members 311 and 35 which form part of the frame. This cover 3| is also provided with a pair of handles I4 which facilitate removal and replacing of the cover 3| with respect to the frame 30.

In the use of the invention the cover 3| is removed from the frame 30 so that a photographic plate may be suitably secured in this frame prior to the taking of a picture. When it is determined what size of photographic plates is to be used, the operator places the upper and lower adjustable support bars in the proper position on the vertical members 34 and 35 of the irame 30. The locations of these adjustable support bars is facilitated by the numerals depicted on the inner edge of the vertical members 34 and 35 as these indicate the size of standard commercial photographic plates. The left hand and right hand plate holders "M and l5 are then positioned longitudinally on the lower insert 53 in a position indicated by numerals depicted on the top edge thereof and which indicates the other dimension of the photographic plate. The left hand and right hand plate holders 14 and 15 are set in a central adjustable position so that later they may be adjusted one way or the other to bring the plate into register when replaced in the frame. The plate is then placed on the satin springs 39 and |05 of the plate holders and the left hand edge of the plate is placed in abutment with the roller 98 on the left hand plate holder 'Hl and the front face of the plate at top and bottom rest against the fiat holding strips 59 and the spring catch 60 engages the top edge of this plate to- Wards the center thereof. The plate is now held in position in the frame 30 and this eliminates any possible chance of the same moving. The plate clamps are then brought down to bear against the rear surface at the top and bottom thereof. In this instance the resilient rollers or cushions are movably adjusted on the rod Gli of the plate clamps so that they bear against the plate as close to the outer edges as possible and the levers 12 are closed and held in position by the spring 'I3 as previously described. The cover 3| is then placed in position on the frame 30 and the camera is ready for use. To remove the plate the plate clamps are opened and the plate is merely removed from its support. Upon replacing of the plate in the camera it will be seen that if necessary slight adjustment of the plate holders '|4 and 15 will provide absolute register. It for any reason further adjustment of the plate is needed to provide for perfect focus the adjustable inserts 52 and 53 may be precisely moved inward or outward with respect to the adjustable support bars as previously set forth, and accordingly slightly altering the distance between the plate and the lens of the camera.

A tool |5 is provided with the adjustable camera back and consists of a handle ||6 in the form of a double hammer head, and a shank H1 fixedly secured in the central portion of this handle and extending outward therefrom at right angles thereto, and a hexagon end tool IIB fixedly secured in the outer end of the shank ||1 and of a size to coincide with all the hexagon holes in the various adjusting nuts, studs, and the like which are used in the construction of the adjustable camera back.

In using the invention as hereinbefore described at the front of the camera instead of the rear the cover 3| is removed from the frame and the various adjustments on the latter, and clamping means may be employed in the same manner as set forth in the foregoing for positioning one or more photographic plates and rigidly securing the same therein.

What I claim is:

l. In an adjustable camera back, a frame, a cover movably secured to said frame, upper and lower adjustable support bars movably secured to said frame, said upper and lower adjustable support bars each having a cutout therein, adjustable inserts located in the cutouts in said upper and lower adjustable support bars, threaded caps iixedly secured to said upper and lower adjustable support bars and extending over the ends of said adjustable inserts, a threaded stud accommodated in each end of said adjustable inserts and being at right angles thereto and engaging said threaded caps thereabove thereby moving the ends of said adjustable insert either inward or outward with respect to said upper and lower adjustable support bars, means on said upper and lower adjustable support bars for mounting a photographic plate, said adjustable inserts permitting forward or rearward adjustment of said photographic plate, plate holders movably supported on said adjustable inserts and providing a means of adjusting said photographic plate vertically and laterally.

2. In an adjustable camera back, a frame, a cover movably secured to said frame, upper and lower adjustable support bars movably secured to said frame, said upper and lower adjustable support bars each having a cutout therein, adjustable inserts located in the cutouts in said upper and lower adjustable support bars, threaded caps iixedly secured to said upper and lower adjustable support bars and extending over the ends of said adjustable inserts, a threaded stud accommodated in each end of said adjustable inserts and being at right angles thereto and engaging said threaded caps thereabove thereby moving the ends of said adjustable inserts either inward or outward with respect to said upper and lower adjustable support bars, means on said upper and lower adjustable support bars for mounting a photographic plate, said adjustable inserts permitting forward or rearward adjustment of said photographic plate, said means comprising flat holding strips fixedly secured to ythe one -side .fof .said adjustable insertsfandjex- :tending past the 4inner edges thereof thus providing a backing against which saidphotographic plate may be held, the lower edge of :said upper adjustable support bar .having a recess ,.therein,

1.a .spring `catch `mounted. on the recessjin said upper adjustablesupport bar and adaptedto enygage the upper edge ofsaid photographic plate When-the sameisplaced in position in saidframe, plate holders movably ysupported, lon :said adjustable insert and providinga means of adjust- 4ing said photographic plate vertically and laterally, .plate clamps mounted onfsaid upper and vlower .adjustable support bars for engaging, said .photographic plate. after thesamehas been suit- -ably .adj usted in position.`

.justable inserts supported on 'said' upperand lower adjustable .support bars Y permitting for- -ward or rearward adjustment .of said -photo- :graphic vplate with `respect yto thefcamera lens -:for bringingthe former. into Vcorrect .focus with the ylatter, and Vplate clamps for substantially 'retaining saidv photographic plate in its adjusted position in said frame, said plateclampsfeach consisting lof a rod' extending parallel to said adjustable support bars, arms movably supporting said rod,.said-rodlbengfxedly secured with Arespect to said arms, .and a bracket secured `to said adjustable support bar and pivotally mounting the opposite endl of said arms, resilient rollers slidably mountedA on saidrod, `a vlever pivotally mounted on said bracket, `and a spring .connecting saidlever. and saidoarmstherebyzproviding a means .of raising .orlowering said arms upon manipulation of said .lever,.;asf-said` lever closed to a certain position the pivot point of the same, and the pivot point of said spring, and the point of connection of said spring to said arms being in line, and as said lever is closed further the pivot point of said spring and said lever thus passing a neutral line and accordingly tending to keep said lever in a closed position and exerting a suitable pressure on said resilient rollers in engagement with said photographic plate.

4. In an adjustable camera back, a frame, a cover movably secured to said frame, Iupper and lower adjustable support bars movably secured to said frame, means on said upper and lower adjustable support bars for mounting a photographic plate, said means comprising adjustable inserts supported on said upper and lower adjustable support bars, and a left hand plate holder and a right hand plate holder movably mounted on said adjustable insert on said lower adjustable support bar, said adjustable insert on said lower adjustable support bar having a plurality of tapped holes suitably spaced apart towards each end thereof, and a plurality of positioning holes located on each side of the tapped holes, said left hand plate holder consisting of a base, a screw extending through a part of said base and engaging any one of the suitably spaced apart tapped holes in said adjustable insert, pins iixedly secured in said base and engaging the positioning holes located on each side of the engaged tapped holes in said adjustable insert, a vertical adjustingy means-mounted .on said .base and cori,- sistng of :a .shaft extending .through a portion thereof, .annger grip :fixedlyfsecured .on the 1 outer -end .of said shaft. isaid shafthaving anannular .groove .cut therein, a retaining Yball l.within said base, a compression spring accommodatedin said base and 'iexertngmressureon said retaining ball thereby engaging ,the same in :the .annular groove .said shaft and :accordingly Permitting .said .shaft to turn .and .at the :same time preventing said shaft from .being removedffrom saidbase,

.a 4pair of stop :pins Afxedly secured .to said .base and :projecting outward ftherefrom g at each .side

o'fsaid shaftfandadapted to engage said linger grip when the same Ais turned a predetermined .distancein .either direction, `an, eccentricv pin -iixedly secured in 4.the inner. .end gof said shaft,

and asatin springlying .over said eccentric pin .and being raised for lowered by the latteras `said shaftis:turnedfthuspreviding a means of vertically adjusting saidsatin springfupon whichsaid 'said second shaftshavingan annular grooverthere.-

lin and ...beingengaged -by said second retaining ball, a .second fingerv grip fixedlyv secured on the v.outer end of said .second shaft, a .second-stop :pin and a .stop strip secured on said base'zand adapted to .engage A said -second finger grip when theY latter is vturned .a .predetermined distance, asecond :eccentric ypin secured I:in ,the inner :end of said secondshaft, and-:afrollerrotatablymounted on-the second eccentric `.pin,jssaid1roller adapt- :ed tol vengage the Ledge `pf Ltheisaidv photographic plate forlaterally adjustingfthe 'position of ithe saine, said .fright ihandaplate :holder :consisting .of a :base having a .satin .spring .supported :there- Aon and operated tby .an eccentric :pin .similar'xto Asaid eccentrictfpin on:saidf base of saidzlefthand .plateholder and :conjunction with tone :aniother providing a means of vertically adjusting one or both sides of said photographic plate supported thereon, and plate clamps mounted on said upper and lower adjustable support bars for substantially retaining said photographic plate in any adjusted position in said frame.

5. In an adjustable camera back, a frame consisting of vertical side members, and horizontal cross members secured to said vertical side members, a cover movably secured to the rear of said frame, upper and lower adjustable support bars movably mounted with respect to said frame, positioning cones secured to said upper and lower adjustable support bars, said vertical side members having cone-like holes therein and adapted to receive said positioning cones on said upper and lower adjustable support bars when the latter are secured in position on said frame, means on said upper and lower adjustable support bars for mounting a photographic plate, said means comprising plate holders movably supported on said lower adjustable support bar and adapted to permit vertical and lateral adjustment of said photographic plate, adjustable inserts mounted in said upper and lower adjustable support bars for permitting depth adjustment of said photographic plate with respect to the camera, and plate clamps mounted on said upper and lower adjustable support bars for substantially holding said photographic plate in position after the adjustment thereof, a fitting as- `sembly extending through one of said vertical -side members and adapted for connection to a Avacuum arrangement, the aforesaid vacuum arrangement being used for holding two photographic plates substantially in contact with one another.

6. In an adjustable camera back, a frame consisting of vertical side members, upper and lowerhorizontal cross members-secured to said vertical side members, a cover movably secured to the rear of said frame, upper and lower adjustable support bars movably mounted with respect to said frame, positioning cones secured to said upper and lower adjustable support bars, said vertical side members having cone-like holes therein and adapted to receive said positioning cones on said upper and lower adjustable support bars when the latter are secured in position on said frame, means on said upper and lower adjustable support bars for mounting a photographic plate, said means comprising plate holders movably `supported on said lower adjustable support bar and adapted to permit vertical and lateral adjustment of said photographic plate, adjustable inserts mounted in said upper and lower adjustable support bars for permitting depth adjustment of said photographic plate with respect to the camera, and plate clamps mounted on said upper and lower adjustable support bars for substantially holding said photographic plate in position after the adjustment thereof, said upper horizontal cross members having a longitudinal groove in the underside towards the front thereof, said cover having a tongue extending along the top edge thereof and adapted for engagement in the longitudinal groove in said upper horizontal cross member when said cover is being placed in position on said frame, a resilient strip adhered to the bottom edge of said cover and tongues extending vertically along the inside face of said cover towards each side thereof, said tongues on the inside face of said cover fitting inside said vertical side members of said frame thus locating said cover laterally with respect to said frame, and said resilient strip on the bottom edge of said cover resting upon said lower horizontal cross member, a pair of fastening pins extending outward from the side edges of said cover, hooks pivotally secured to the outer side of said vertical side members of said frame4 and adapted to engage said pair of fastening pins for substantially holding said cover in position on said frame..

'7. In an adjustable camera back, a frame consisting of vertical side members, and horizontal cross members secured to said vertical side members, upper and lower adjustable support bars movably mounted with respect to said frame, positioning cones secured to said upper and lower adjustable support bars, said vertical side members having cone-like holes therein and adapted to receive said positioning cones on said upper and lower adjustable support bars when the latter are secured in position on'said frame, means on said upper and lower adjustable support bars for mounting a photographic plate, said means comprising plate holders movably supported on said lower adjustable support bar and adapted to permit vertical and lateral adjustment of said photographic plate, adjustable inserts mounted in said upper and lower adjustable support bars for permitting depth adjustment of said photographic plate with respect to the camera, and plate clamps mounted on said upper and lower adjustable support bars for substantially holding said photographic plate in position after the adjustment thereof. l A

CRESSWEU.. REDVERS GREGORY.

REFERENCES CITED The following references are of record in the ille of this patent:

UNITED STATES PATENTS 

